Electronically-actuated cementing port collar

A port collar for use on casing in a borehole, the port collar comprising:

• a housing disposed on the casing and having an internal bore, the housing having at least one exit port communicating the internal bore with the borehole;
• an opening valve disposed in the housing and being biased from a closed position to an opened position relative to the at least one exit port;
• a closing valve disposed in the housing and being biased from an opened position to a closed position relative to the at least one exit port;
• and
• an electronic controller operatively coupled to the opening and closing valves, the electronic controller activating the bias of the opening valve from the closed position to the opened position in response to a first trigger, the controller activating the bias of the closing valve from the opened position to the closed position in response to a second trigger.

A method of operating a port collar on casing in a borehole, the method comprising:

• holding open a closing valve on the port collar biased in a closed position relative to at least one port on the port collar;
• holding closed an opening valve on the port collar biased in an opened position relative to the at least one port;
• releasing open the opening valve biased to the opened position in response to a first trigger downhole at the port collar;
• and
• releasing closed the closing valve biased to the closed position in response to a second trigger downhole at the port collar.

A method of operating a port collar on casing in a borehole, the method comprising:

• responding to a first electronic trigger downhole at the port collar;
• moving, in response to the first electronic trigger, an opening valve on the port collar by biasing the opening valve from a closed position to an opened position relative to at least one port on the port collar;
• responding to a second electronic trigger downhole at the port collar;
• and
• moving, in response to the second electronic trigger, a closing valve on the port collar by biasing the closing valve from an opened position to a closed position relative to the at least one port.